I'm trying to create a newletter group in the OptIn modules and I get this error...

The INSERT statement conflicted with the FOREIGN KEY constraint "FK_iwebs_BE_EmailGroups_Modules". The conflict occurred in database "xxxxxxxxxDB", table "dbo.Modules", column 'ModuleID'. The statement has been terminated.

Has anyone got an idea why this is? I'm using bulk email without any issue on another installation of DNN. error is on DNN5.4.4.